The Benfleet flood barrier was opened in 1983. It was built to help protect low lying areas of Canvey Island and Benfleet, such as Hopes Green, from flooding.
The main part of the flood defences is a raised sea wall around Canvey Island. In this part of the creek it was considered better to build a barrier at each end, these being East Haven barrier and Benfleet barrier.
Planning for the barriers began in 1972 and was part of a scheme to raise the Canvey sea wall and build the Thames barrier. Work started on the Benfleet barrier in 1980 during the steel strike and was completed in 1983 at a cost of twelve million pounds. As they needed to build a cofferdam, the contractors imported and used Dutch steel. The dam was built during the summer of 1980. Contractors had to pile down over 100 feet in order to reach the bedrock under Benfleet’s clay.
The barrier is 90m wide and 10m high, with 3 openings, each 13m wide. Each opening contains a top hinged flap gate weighing 30 tons. For normal tides the gates are left in the raised position. In the event of a tide predicted to be higher than 3.4m at Southend, the gates are lowered to a vertical position using anchor chains. Two winch motors, costing around £20million, operate the mild steel gates using a hydraulics system and 170-bar pressure – which equates to 2,466lbs per square inch. A 106hp engine powers the barrier itself and if that fails, a backup engine is on standby.
The barrier was officially opened by the Treasury Secretary, John Wakeham M.P. on 25th February 1983.
On the 9th March, 2011 there was an open day for visitors to view the workings of the barrier. Benfleet Community Archive took advantage of this and recorded the occasion on video.